The Impact of Parental Military Deployment on Children with Disabilities Long wartime assignments put unprecedented pressures on the U.S. Armed Forces and their families. [Although the pace of deployments have been reduced recently, it remains critical to understand the impact of deployment as U.S. Armed Forces are routinely called to conflicts around the globe.] Despite high levels of resilience among military families, they remain at risk for stress-related outcomes and, relative to parental deployment, some research has found that children have experienced increases in visits for depressive disorders, sleep disorders, and anxiety, and greater use of psychotropic medications. Although these findings foreshadow possible greater negative consequences of deployment for children with disabilities who generally utilize more services, this group has not been separately studied. Life course transitions are often major stressors on families of children with disabilities and are associated with additional negative child outcomes. The proposed R21 study is in response to PA-11-202 [Research on Children in Military Families: The Impact of Parental Military Deployment and Reintegration on Child and Family Functioning] and the Specific Aims are to (1) analyze longitudinal military health system data to describe health care utilization patterns among children of military members with significant disabilities; (2) conduct multivariate difference-in-difference analysis to assess the association of deployment on these utilization patterns; and (3) test whether aspects of the family environment during deployment buffer or exacerbate the effect of deployment on these utilization patterns. The study will focus on children with autism, children with bipolar disorder, children with motor impairments and children with intellectual and developmental disabilities identified by diagnoses contained on healthcare claims. The proposed study is innovative in its approach to understanding the impact of parental deployment. First, we will focus on a carefully defined population of children with significant and specific types of disabilities. Second, we have access to existing, longitudinal, unusually comprehensive data on each child. Third, we will construct a wide range of discrete health care utilization measures, some of which will reflect routine and preventative services, some reflecting special need services, and others that may be indicative of crisis or emergency needs. Fourth, although by necessity all studies of deployment must be based on observational rather than experimental data, we will utilize a particularly strong, quasi-experimental design based on difference in difference multivariate analysis of pre-post measures of two non-equivalent groups. Finally, we are designing the study and will interpret our results based on a conceptual model that assesses the relation between aspects of the family environment and critical outcomes, a model developed by project team members. The findings will provide necessary information for TRICARE, the health system of the Department of Defense, to evaluate the unique needs of military families of children with significant disabilities and generate specific recommendations regarding needed interventions to support families and children during deployments.